Airplane and control device therefor



Aug. 7, 1945.

F.- MAXWELL AIRPLANE AND CONTROL DEVICE THEREFOR Original Filed Nov. 12; 1940 Patented Aug. 7, 1945 AIRPLANE AND ooN'rRoL DEVICE THEREFOR Frank R. Maxwell, Rose Valley, Pa.

Original applicationlNovember 12, 1940, Serial No.

Divided and this application March 17, 1943, Serial N0. 479,43Q I 3 Claims. (Cl. 244-42)" 1 My present invention relates-to airplanes and. more particularly has reference to an airplane winghaving a novel slot and flap so interconnected that the opening movement of the slot is under positive control of the pilot at all times. More specifically, the slot is locked in its closed position against aerodynamic forces acting on thenose of the wing until the pilot moves the fl p .t a "Numerous control devices have heretofore been incorporated in airplane Wings to permit a high speed in flight and at the same time enable low speed .takeoffs and permit the airplane to land inrelativelysmall area's. j

An object of this invention is to provide an airplane wing' having a slot. Which extends through the wing adjacent to the leading edge thereof with covers for the upper andl'ower openings of saidslot, said covers in their closed position "conforming to the upper and lower contours of the wing and means to move the lower cover intocontact with .the upper' cover to give an airfoil se'ction to the upper cover upon initial movement of the upper cover and to maintain this airfoil, section during. all further movement of the upper cover, thereby affording optimumtair flow through the slot.

Yet another object of this invention is to provide a novel nose slot for an airplane wing in which the upper and lower openings of the slot are closed by covers and in which the lower cover can open sufficiently to afiord a smooth contour in the slot when the upper cover is partially opened and to thereafter remain in such position so that the contour of the slot will remain smooth as the upper cover is opened further.

And a still further object of this invention is to provide a slot for an airplane wing in which the upper and lower openings of the slot are closed by cover members, the upper cover member being pivoted to the nose of the wing and the lower cover member being hinged to the upper cover member.

To achieve the foregoing and other objects, this invention comprises providing a slot adjacent to the leading edge of the wing and a flap near the trailing edge of the wing. The upper and lower openings of the slot are adapted to be closed by covers which conform to the contour of the upper and lower surfaces of the wing in their closed position. Linkage connects the flap to the upper cover and there is a connection tothe lower cover which is operated by movement of the linkage. A control extends from the operating linkage to the cockpit or the fuselage of the airplane so thatthe pilot may actuate the slot and flap by a single control. A

The linkage is of. such nature that the flap may move througha small angle before the slot opensandtheaerodynamic forces working on the leading. edge of the. wing cannot open the upper cover until the pilot has moved the flap, Furthermore, the connectionto the lower cover will permit the lower coverto move into contact with the upper cover to give an airfoil section to the upper cover upon the initial movement of the-upper cover and will maintain this airfoil section for all further movement-0f theupper cover, thus permitting maximum airflow through theslot. I

Inthe drawing: 4

Figure 1 is-a transverse sectionalview of a form of fm'y-novel nose slot and. flap combination.

, [Figure 2 is aflf'ragmental transverse sectional view of the constructionshownin Figure 1 illus trating the different movements of the slot covers. 1 Referring to Figures v1 and I2 I have shownan airplane wing I of any suitable construction having internal spars 2, a slot 3. "which extends through the wing adjacent to the leading edge thereofv and a flap}, provided near thettrailing edge; of the wing, The wing I is formed with a recess or, well 5 in which the fiapd is pivoted as shown 'at B. An arm I is attached to the flap and an operating rod 8 is pivoted to the free end of the arm I as indicated at 9. The rod 8 is suitably connected to the flap operating mechanism (not illustrated) located within the cockpit or fuselage of the airplane.

There is also attached to the flap 4 a short arm I0 to which is pivoted at I I a long operating link or push rod I2. As clearly shown in Figure 1, the operating rod I2 extends to a point adjacent to the slot 3 and is pivoted at I3 to one arm of a lever which is pivoted at BI to the internal structure of the wing.

The upper opening of the slot 3 is adapted to be closed by a cover I6 which is hinged to the nose of the wing I, as shown at H. A second slot cover I8 for the lower opening of the slot i also hinged at the point II. As clearly shown in the drawings, when the covers I6 and I8 are in their closed positions, they conform to the contour of the upper and lower surfaces of the wing I, thereby affording an airfoil section.

A push rod 62 is pivoted to the lever 60 as shown at 63, and to the upper slot cover as shown at 64. The rod 62 is curved as indicated at 65 so that it will not interfere with the pivot point 6| of the lever 60.

the flap 4, the rod II will slide in the sleeve 68,:

compressing the spring 69, thereby causingv the lower slot cover l8 to move into well or recess 3| as shown in broken lines in Figure 2 on initial movement of the upper cover whereby a smooth contour is provided in the slot 3.

It should be further observed thatthe pivot, points I 3, 6| and 63 are in a substantially straight line when the slot 3 and the flap 4 are in their closed positions. As a result, it is not possible for the upper slot cover 16 to be openedby virtue of the forces acting on the wing I From the foregoing description, it will bear)- preciated that the slot is provided with upper and lower covers having means to move the lower cover into contact with the upper cover to give an airfoil 1 section to the upper cover upon initial movement of the upper cover andto maintain this airfoil section during allfurther movement of the upper cover. In addition, the upper cover under certain circumstance may be pivoted to the nose of the wing and'the lower cover may be hinged to the upper cover. The linkage connecting the slot and flap may be provided with a locking device to prevent the aerodynamic forces acting on the, wing from opening the slot until the flap begins to While I have shown and described the preferred embodiment of my invention, Iwish it to be understood that I do not/confine myself to the precise details of construction herein set forth by way of illustration, as it is apparent that many changes and variations may be made therein, by those skilled in the art, without departing from the spirit of the invention, or exceeding the scope of the appended claims. This application is a division of application filed by me November 12, 1940, Serial No. 365,347, now Patent No. 2,321,837, granted June l, 1943.

What I claim and desire to protect by Letters Patent is:

1. An airplane wing having a slot adjacent its leading edge extending transversely to the line of flight, an upper cover for the slot pivotally supported from the wing, a lower cover for the slot, and interconnected members forming operative connections between said covers whereby they may be rendered cooperatively operative, said :rioperative connections between the upper and lower slot covers comprising means whereby the lower cover will be initially moved toward its open position before initial eifective opening movement of the upper cover and whereby the lower cover will remain in fully opened position throughout the range of effective opening of the upper cover.

2. An airplane wing having a, slot adjacent its leading edge extending transversely to the line of flight, an upper cover for the slot pivotally supported from the wing, a lower cover for the slot, and interconnected members forming operative connections between said covers whereby they may be rendered cooperatively operative, said operative connections between the upper and lower slot covers comprising means permitting lost motion' whereby the lower cover will be initially moved toward its position before initial eiIective opening movement of the upper cover and whereby the lower cover will remain in fully opened position throughout the range of effective opening of theupper cover. 3. An airplane wing havin'ga slot adjacent its leading edge extending transversely to the line of flight, an upper cover for the slot pivotally supported from the wing, a lower cover for the slot, hinged to the upper cover, and interconnected members forming operative connections between said cover whereby they'may be rendered co-f operatively operative, said operative connections between the upper and lower slot covers comprising means whereby the lower cover will be initially moved toward its open position before initial effective opening movement of the upper cover and wherebythe lower cover will remain in fully opened position throughout the range of efiective opening of the upper cover.

FRANK R. MAXWELL. 

